An old horizontal twin steam engine, commercially built with good proportions. It's a small full-size engine rather than a model, probably used in a small workshop to provide power.
An interesting restoration project - whilst there are parts missing, most have their partner on the other cylinder still present to be used as patterns. These include valve chest cover, eccentric strap and rod and slide bars with supporting pillars.
Both connecting rods are missing, complete with brasses.
Overall, although grubby, what remains is in good condition under a light surface coating of rust.